Ocean thermal energy conversion systems are systems that generate electricity by harnessing the difference in the temperature of the ocean at the surface and the temperature of the ocean at depth.
Sunlight cannot penetrate deep in the ocean, and, therefore, the temperature deep in the ocean is constantly cold. In contrast, the water at the surface is heated by the sun and is warmer. A heat engine uses this temperature difference to create kinetic energy, which can be used, for example, to generate electricity.
As the temperature difference between the cold water and the warm water increases, the efficiency of the heat engine increases. One way to effectively harness the temperature difference between the cold water and the warm water is to place the heat engine and the heat exchangers as far from one another as possible. This means placing the cold water heat exchanger as deep in the water as possible.
The problem with placing the cold water heat exchanger deep in the ocean is maintaining the heat exchanger. In order to operate these systems effectively, the heat exchangers must be cleaned and maintained regularly. Sea water is highly corrosive to the metal used in heat exchangers, causing oxidation and leaks. Another problem is that ocean life, like barnacles and seaweed, grow on the heat exchangers. This is difficult and costly to do when the heat exchangers are deep in the ocean.
FIG. 1 depicts a schematic diagram of the salient components of an ocean thermal energy conversion system in the prior art. FIG. 1 comprises heat engine 101, pipe 102-1, pipe 102-2, heat exchanger 103, and water surface 104.